James and the Giant Corn Rotating Header Image

June 17th, 2015:

Albino Corn

What’s wrong with this picture? (The title should have given you a hint.)

Albinos

Here, I’ll zoom in.

IMG_3501-closeup

These five plants should all be nearly genetically identical (from a single inbred line).

Lots of different things can cause albino corn. From defects in chlorophyll (the pigment that plants plants green) biosynthesis to defects in how the chloroplasts themselves (the plant organelles where photosynthesis happens) divide. One of the frankly awesome things about working with corn is that these sorts of mutants actually survive long enough to study, even though most (all?) of them ultimately prove lethal. In arabidopsis, mutations of most of the same genes wouldn’t even survive through germination.¬†Alice Barkan’s lab estimates there are ~600 maize genes whose mutation produce¬†reductions in chlorophyll (generally resulting in either yellow or white plants). <– click that link if for no other reason than to see a frankly beautiful photo showing the variation in shades of maize seedlings from healthy green through sickly yellow to pure snow white.

All that said: when you start seeing albino plants pop out in a batch of what should be genetically identical plants (all from the same inbred line), it’s a pretty good sign that particular batch of seeds is hiding some unrecorded complexity rather recently within its family tree.